The present invention relates to the nucleotide sequences of Fos regulated genes, the proteins encoded by the sequences, uses of the sequences and encoded proteins, and transgenic animals comprising one or more of the sequences. The present invention also relates to antibody molecules having affinity for the encoded proteins and uses of the antibody molecules, and antisense nucleotide molecules and uses of the antisense nucleotide molecules.
The transcription factor AP-1 is involved in a number cellular processes, including cell proliferation, differentiation, and neuronal function (see Angel and Karin (1991) Biochim. Biophys. Acta 1072:129-57). AP-1 is considered to exert its effect by binding to a DNA recognition sequence, known as the AP-1 element, found in the promoter and enhancer regions of genes. The AP-1 element has the consensus sequence in TGA G/C TCA.
A number of genes have been found which contain AP-1 elements in their regulatory regions including c-Jun (Angel et al. (1988) Cell 55:875-885), MCP-1 (Rollins et al. (1988) Proc. Natl. Acad. Sci. USA 85:3738-3742), Stromelysin (Kerr et al. (1988) Science 242:1424-1427), Type I collagenase (Schonthal et al. (1988) Cell 54:325-334), and Interleukin II (Farrar et al. (1989) Crit. Rev. Ther. Drug Carrier Syst. 5:229-261). AP-1 is composed of dimeric complexes formed between Jun (c-Jun, Jun-B, and Jun D) and Fos (c-Fos, Fos B, Fra-1, and Fra-2) proteins. The Fos component of AP-1 has been found to be the limiting component of AP-1 activity in cycling cells (see Kovary and Bravo (1991) Mol. Cell. Biol. 11:2451-2459; Kovary and Bravo (1991) Mol. Cell. Biol. 11:4466-4472).
c-Fos is a nuclear proto-oncogene which has been implicated in a number of important cellular events, including cell proliferation (Holt et al. (1986) Proc. Natl. Acad. Sci. USA 831:4794-4798; Riabowol et al. (1988) Mol. Cell. Biol. 8:1670-1676), differentiation (Distel et al. (1987) Cell 49: 835-844; Lord et al. (1993) MoL Cell. Biol. 13:841-851), and tumorigenesis (Cantor et al. (1993) Proc. Natl. Acad. Sci. USA 90:10932-10936; Miller et al. (1984) Cell 36:51-60; Ruther et al. (1989) Oncogene 4:861-865). c-Fos encodes a 62 kDa protein which forms heterodimers with c-Jun, forming an AP-1 transcription factor which binds to DNA at an AP-1 element and stimulates transcription. Fos gene products can also repress gene expression. Sassone et al. (1988) Nature 334:314-319 showed c-Fos inhibits its own promoter, and Gius et al. (Gius et al. (1990) Mol. Cell. Biol. 10:4243-4255) and Hay et al. (1989) Genes Dev. 3:293-303 showed c-Fos inhibits early response genes Egr-1 and c-myc. AP-1 factors have also been shown to inhibit expression of the MHC class I and PEPCK genes (see Gurney et al. (1992) J. Biol. Chem. 267:18133-18139 and Howcroft et al., 1993).
It can therefore be seen that Fos regulated genes are extremely important for the correct expression of genes which lead to changes in the cell phenotype. The importance of Fos genes was clearly demonstrated by generating mice deficient in c-Fos (see Hu et al. (1994) EMBO J. 13: 3094-3103). The c-Fos deficient mice were viable, but displayed a range of tissue-specific developmental defects, including osteopetrosis, delayed gametogenesis and lymphophenia, and behavioral abnormalities.
The c-Fos deficient mice were used to generate fibroblast cell lines and the expression of two genes was found to be abnormally low. The two genes were Stromelysin and Type I collagenase. Both genes were previously identified as having AP-1 sites in their regulatory sequences (see Kerr et al. (1988) Science 242:1424-1427 and Schonthal et al. (1988) Cell 54:325-334). Stromelysin and Type I collagenase have been implicated in embryonic tissue development (Brenner et al. (1989) Nature 337:661-663), injured tissue remodelling (Hasty et al. (1990) Arthritis Rheum. 33:388-397; Woessner and Gurja (1991) J. Rheumatol. Suppl. 27:99-101), and in tumor progression and metastasis (Liotta and Stetler (1990) Semin. Cancer Biol. 1:99-106).
Superti-Furga et al. (1991) Proc. Natl. Acad. Sci. USA 88:5114-5118 showed that c-Fos activity can be controlled hormonally by fusing the mouse c-Fos protein to the ligand binding domain of the human estrogen receptor. The fusion protein was found to stimulate AP-1 dependent transcription in a strictly hormone-dependent manner. Using the fusion protein an AP-1 regulated gene, Fit-1, was found. Fit-1 was found to encode a secreted or membrane bound protein depending on the splicing pattern.
The present invention relates to the nucleotide sequences encoding two novel Fos regulated genes. The present invention provides a nucleotide molecule encoding a protein encoded by a Fos regulated gene or a fragment thereof, wherein said protein or fragment thereof is encoded by a nucleotide sequence shown in FIG. 1 (SEQ ID NO:1) or 2 (SEQ ID NO:3), or a fragment thereof, including allelic variants and species variants of the nucleotide sequences.
The term “nucleotide molecule” used herein refers to nucleotides of any length, either ribonucleotides or deoxyribonucleotides. The term encompasses both double and single stranded molecules. It also includes known types of modifications, for example labels which are known in the art, methylation, “caps”, substitution of one or more of the naturally occurring nucleotides with an analog, internucleotide modifications such as, for example those with uncharged linkages (e.g., methyl phosphonates, phosphotriesters, phosphoamidates, carbamates, etc.) and with charged linkages (e.g., phosphorothioates, phosphorodithioates, etc.), those containing pendant moieties, such as, proteins (including nucleases, toxins, antibodies, signal peptides, poly-L-lysine, etc.), those containing intercalators (e.g., acridine, psoralen, etc.), those containing chelators (e.g., metals, radioactive metals, boron, oxidative metals, etc.), those containing alkylators, and those containing modified linkages (e.g., alpha anomeric nucleic acids, etc.).
The nucleotide molecule of the present invention may encode the protein of a Fos regulated gene or a fragment thereof. The term “fragment” used in relation to the proteins refers to fragments which are of sufficient length to be unique to the presently claimed protein (e.g., 10, 15, 20, or 25 consecutive amino acids in length). Preferably, the protein fragments are capable of eliciting at least part of an activity of the full protein. Particularly preferred fragments comprise a conserved region of a gene which has been found to be homologous with a number of other genes. Such conserved regions are considered to have a specific function.
The nucleotide sequences shown in FIGS. 1 (SEQ ID NO:1) and 2 (SEQ ID NO:3) will, as with most naturally occurring nucleotide sequences, have a number of other forms, such as allelic variants and species variants. Such variants and any other naturally occurring forms of the nucleotide sequences of the present invention are also considered to form a part of the present invention. Such variants should have at least 60%, preferably 80%, and most preferably 90% sequence homology with the sequence shown in FIG. 1 (SEQ ID NO:1) or 2 (SEQ ID NO:3) or fragments thereof.
The present invention also relates to the nucleotide molecule of the present invention wherein the protein or a fragment thereof encoded by the sequence shown in FIG. 1 (SEQ ID NO:1) or 2 (SEQ ID NO:3) or a fragment thereof is altered. Preferred altered proteins or fragments thereof, are those that still retain their activity and preferably have a homology of at least 80%, more preferably 90%, and most preferably 95% to the protein or a fragment thereof encoded by the sequence shown in FIG. 1 (SEQ ID NO:2) or 2 (SEQ ID NO:4) or a fragment thereof. Preferably such altered proteins or fragments thereof differ by only 1 to 10 amino acids. It is further preferred that the amino acid changes are conservative. Note that FIG. 2 sets forth alternate reading frames (SEQ ID NOS: 17, 53, and 69) for the nucleotide sequence therein (SEQ ID NO: 3), which encode the corresponding predicted polypeptides (polypeptides SEQ ID NOS: 18-52 for SEQ ID NO: 17, polypeptides SEQ ID NOS: 54-68 for SEQ ID NO: 53, and polypeptides SEQ ID NOS: 70-90 for SEQ ID NO: 69) set forth in the figure.
Conservative changes are those that replace one amino acid with one from the family of amino acids which are related in their side chains. For example, it is reasonable to expect that an isolated replacement of a leucine with an isoleucine or valine, an aspartate with a glutamate, a threonine with a serine, or a similar conservative replacement of an amino acid with a structurally related amino acid will not have a major effect on the biological activity of the protein.
However, it is sometimes desirable to alter amino acids in order to alter the biological activity of the protein. For example, mutations which abolish or enhance one or more of the functions of the protein can be particularly useful. Such mutations can generally be made by altering any conserved sequences of protein. Mutations which increase the number of amino acids which are capable of forming disulphide bonds with other amino acids in the protein are particularly preferred in order to increase the stability of the protein. Mutations which decrease the number of amino acids which are capable of forming disulphide bonds with other amino acids in the protein may also be made if it is desired to decrease the stability of the protein. It is preferred that such altered proteins or fragments thereof have a homology of at least 80%, more preferably 90%, and most preferably 95% to the protein or a fragment thereof encoded by the sequence shown in FIG. 1 (SEQ ID NO:2) or 2 (SEQ ID NO:4) or a fragment thereof. Preferably such altered proteins or fragments thereof differ by only 1 to 10 amino acids.
The nucleotide molecule of the present invention can be obtained by methods well known in the art. For example, the sequences may be obtained by genomic cloning or cDNA cloning from suitable cell lines or from DNA or CDNA derived directly from the tissues of an organism, such as a mouse. Suitable cell lines include any fibroblast cell lines such as the 3T3 cell line, described by Hu et al. (1994) EMBO J. 13: 3094-3103. Positive clones may be screened using appropriate probes for the nucleotide molecule desired. PCR cloning may also be used. The probes and primers can be easily generated given that the sequences encoding the protein or a fragment thereof encoded by the nucleotide molecule of the present invention are given herein.
Numerous standard techniques known in the field of molecular biology may be used to prepare the desired nucleotide molecules or the probes and primers for identifying the positive clones. The nucleotide molecules probes or primers may be synthesized completely using standard oligonucleotide synthesis methods, such as the phosphoramidite method.
Numerous techniques may be used to alter the DNA sequence obtained by the synthesis or cloning procedures, and such techniques are well known to those skilled in the art. For example, site directed metagenesis, oligonucleotide directed mutagenesis, and PCR techniques may be used to alter the DNA sequence. Such techniques are well known to those skilled in the art and are described in the vast body of literature known to those skilled in the art, for example Sambrook et al. (1989) Molecular Cloning: A Laboratory Manual (Cold Spring Harbor Laboratory Press, Cold Spring Harbor, N.Y.).
The present invention further provides the protein encoded by the nucleotide molecule of the present invention. Preferably, the protein encoded by the nucleotide molecule of the present invention has the amino acid sequence shown in FIG. 1 (SEQ ID NO:2) or 2 (SEQ ID NO:4), or a fragment thereof.
The term “protein” as used herein refers to a polymer of amino acids and does not refer to a specific length of the product; thus, peptides, oligopeptides, and proteins are included within the term protein. The term also does not refer to or exclude post-expression modifications of the protein, for example, glycosylations, acetylations, and phosphorylations. Included in the definition are proteins containing one or more analogs of an amino acid (including for example, unnatural amino acids), proteins with substituted linkages, as well as other modifications known in the art, both naturally occurring and synthesized.
The protein of the present invention can be obtained from cells that naturally produce the protein such as fibroblast cells using standard purification techniques. However, it is preferred that a suitable host cell and vector system is used for the expression of the nucleotide molecule of the present invention. The nucleotide molecule of the present invention can be expressed in a variety of different expression systems, for example, those used with mammalian cells, baculoviruses, bacteria, and eukaryotic microorganisms such as yeasts.
All the above-mentioned expression systems are known in the art, and expressing nucleotide sequences is now a standard technique known to all skilled in the art. Preferably, eukaryotic, e.g., mammalian, host cell expression systems are used. In particular, suitable mammalian host cells include Chinese hamster ovary (CHO) cells, HeLa cells, baby hamster kidney (BHK) cells, cells of hepatic origin such as HepG2 cells, and myeloma or hybridoma cell lines.
The present invention further provides a vector for the expression of the nucleotide molecule of the present invention, comprising a promoter and the nucleotide molecule of the present invention. A mammalian promoter can be any DNA sequence capable of binding mammalian RNA polymerase and initiating the downstream transcription of a coding sequence into MRNA. Particularly useful promoters are those derived from mammalian viral genes, such as the SV40 early promoter, adenovirus major late promoter, and the herpes simplex virus promoter. Additionally, sequences from non-viral genes can also be used as promoters, such as from the murine metallothionein gene.
The nucleotide molecule of the present invention may be expressed intracellularly in mammalian cells. A promoter sequence may be directly linked with the nucleotide molecule of the present invention, in which case the first amino acid at the N-terminus of the encoded protein will be a methionine encoded by the start ATG codon.
Alternatively, the protein encoded by the nucleotide molecule of the present invention can be secreted from the cell by linking a nucleotide sequence encoding a leader sequence to the nucleotide molecule of the present invention. The encoded fusion protein will comprise a leader sequence fragment and the protein encoded by the nucleotide molecule of the present invention. The leader sequence will lead to the secretion of the fuision protein out of the cell. Preferably, there are processing sites between the leader sequence and the protein encoded by the nucleotide molecule of the present invention allowing the leader sequence to be cleaved off enzymatically or chemically. An example of such a leader sequence is the adenovirus triparite leader.
The vector of the present invention is preferably a nucleic acid vector comprising DNA. The vector may be of linear or circular configuration and can be adapted for episomal or integrated existence in the host cell, as set out in the extensive body of literature known to those skilled in the art. The vectors may be delivered to cells using viral or non-viral delivery systems. The choice of delivery system will determine whether the DNA molecule is to be incorporated into the cell genome or remain episomal.
The vector of the present invention can comprise further control elements such as polyadenylation signals, transcription termination signals, enhancers, locus control regions (LCRs), etc.
The present invention further provides a host cell transformed with the vector of the present invention. Transformation refers to the insertion of an exogenous polynucleotide into a host cell, irrespective of the method used for the insertion, for example, direct uptake, transduction, f-mating, or electroporation. The exogenous polynucleotide may be maintained as a non-integrated vector (episome), or may be integrated into the host genome. Preferably, the host cell is a eukaryotic cell, more preferably a mammalian cell, such as Chinese hamster ovary (CHO) cells, HeLa cells, baby hamster kidney (BHK) cells, cells of hepatic origin such as HepG2 cells, and myeloma or hybridoma cell lines.
The present invention further provides a method for producing the protein encoded by the nucleotide molecule of the present invention, comprising transfecting a host cell with the vector of the present invention, culturing the transfected host cell under suitable conditions in order to lead to the expression of the DNA molecule and the production of the desired protein. The protein may then be harvested from the transfected cells or from the cell growth media, depending on whether the protein is secreted, using standard techniques.
The present invention further provides the nucleotide molecule of the present invention for use in therapy.
The present invention further provides the use of the nucleotide molecule of the present invention in the manufacture of a composition for the treatment of developmental disorders.
The present invention further provides the use of the nucleotide molecule of the present invention in the treatment of developmental disorders.
Fos regulated genes are known to be involved in development and cell differentiation. Accordingly, the discovery of genes regulated by Fos has implications in the control of development and cell differentiation.
The nucleotide sequences shown in FIG. 1 (SEQ ID NO:1) and FIG. 2 (SEQ ID NO:3) have been found to have a similar sequence to genes of a family of growth factors characterized by the Platelet Growth Factor (PDGF) family signature. The most clearly related sequence is that of the Vascular Endothelial Growth Factor (VEGF). VEGF forms a homodimer which is a growth factor active in angiogenesis and endothelial cell growth (see Keck et al. (1989) Science 246:1309-1311 and Leung et al. (1989) Science 246:1306-1309). VEGF has also been used to stimulate angiogenesis and thereby produce a therapeutic effect (see Takeshita et al. (1994) J. Clin. Invest. 93:662-670).
The protein encoded by the nucleotide sequence (SEQ ID NO:1) in FIG. 1 is a mouse protein and the protein encoded by the nucleotide sequence (SEQ ID NO:3) in FIG. 2 is the human homologue of the mouse protein encoded by the sequence given in FIG. 1. Both the proteins are herein referred to as c-Fos Induced Growth Factor (FIGF).
The use of the nucleotide molecule of the present invention in therapy can therefore be seen to be an important application of the sequences of the Fos regulated genes of the present invention.
The nucleotide sequences shown in FIG. 1 (SEQ ID NO:1) and FIG. 2 (SEQ ID NO:3) are of particular interest in lung disorders as it is has been found that the nucleotide sequences are mainly expressed in the lungs. Particular lung disorders which may be treatable using the nucleotide molecule encoding the protein or fragments thereof which are encoded by the sequence shown in FIG. 1 (SEQ ID NO:1) or FIG. 2 (SEQ ID NO:3), include pneumonia and pneumoconiosis. The nucleotide molecule may also be used following pneumonectomy in order to aid in lung re-growth.
The nucleotide sequence in FIG. 2 (SEQ ID NO:3) has been mapped to human chromosome Xp22, near the locus that maps for the pathology spondyloepiphyseal dysplasia (SEDL). The genetic map of this region is described by Ferrero et al. (Ferrero et al. (1995) Human Molecular Genetics 4:1821-1827) and the mapping of the SEDL disease is described by Heuertz et al. (1993) Genomics 18:100-104. SEDL may therefore be treatable using the nucleotide molecule encoding the protein or fragments thereof, which are encoded by the nucleotide sequence given in FIG. 1 (SEQ ID NO:1) or in FIG. 2 (SEQ ID NO:3).
As previously discussed, Fos regulated genes have been found to be involved in tumor progression and metastasis. By inhibiting Fos regulated genes it is possible to inhibit or suppress tumor growth.
Previously Kim et al. (Kim et al. (1993) Nature 362:841-844) suppressed tumor growth by injecting monoclonal antibodies specific for VEGF. As stated previously, VEGF has a similar nucleotide sequence to the nucleotide sequences shown in FIG. 1 (SEQ ID NO:1) and FIG. 2 (SEQ ID NO:3). Accordingly, by inhibiting either the in vivo expression, translation, etc. of the native nucleotide molecules of the present invention, tumor growth may be inhibited or suppressed.
The actions of the Fos regulated genes corresponding to the nucleotide molecules of the present invention may be inhibited by a number of techniques. Preferred techniques include antisense-based techniques, ribozyme-based techniques, and antibody-based techniques.
Antibody molecules having specificity for the protein encoded by the nucleotide molecules of the present invention can be used to block the function of the protein and thereby inhibit or suppress tumor growth.
The present invention further provides antibody molecules having specificity for the protein of the present invention. The antibody molecules may be a complete polyclonal or monoclonal antibody or antigen-binding fragments, such as Fv, Fab, F(ab′)2 fragments and single chain Fv fragments thereof. The antibody molecule may be a recombinant antibody molecule such as a chimeric antibody molecule preferably having human constant regions and mouse variable regions, a humanized CDR-grafted antibody molecule or fragments thereof. Methods for producing such antibodies are well known to those skilled in the art and are described in EP-A-0120694 and EP-A-0125023.
The present invention further provides the antibody molecule of the present invention for use in therapy.
The present invention also provides the use of the antibody molecule of the present invention in the manufacture of a composition for the treatment of proliferative diseases such as cancer.
The present invention further provides the use of the antibody molecule of the present invention for the treatment of proliferative diseases such as cancer.
The present invention further provides an antisense nucleotide molecule or a fragment thereof, having the complementary sequence to the nucleotide molecule or a fragment thereof, of the present invention. The antisense nucleotide molecule of the present invention can be generated using the same standard techniques as for the nucleotide molecule of the present invention.
The present invention further provides an antisense vector for the expression of the antisense nucleotide molecule of the present invention comprising a promoter and the antisense nucleotide molecule. The antisense vector is identical to the nucleic acid vector of the present invention except that the vector contains the antisense nucleotide molecule of the present invention.
The present invention further provides the antisense vector of the present invention for use in therapy.
The present invention further provides the use of the antisense vector of the present invention in the manufacture of a composition for the treatment of cell proliferative diseases such as cancer.
The present invention further provides the use of the antisense vector of the present invention in the treatment of cell proliferative diseases such as cancer.
The present invention further provides a vector for the expression of a ribozyrne, comprising a promoter and a nucleotide sequence encoding a ribozyme capable of cleaving the RNA transcript of the nucleotide molecule of the present invention. The vector encoding the ribozyme is identical to the vectors previously described except that the vector encodes a ribozyme. The ribozyme being capable of cleaving the RNA transcript of the nucleotide molecule of the present invention. Techniques for producing such ribozymes are known to those skilled in the art and are discussed in Cantor et al. (Cantor et al. (1993) Proc. Natl. Acad. Sci. USA 90:10932-10936).
The present invention further provides the ribozyme-encoding vector of the present invention for use in therapy.
The present invention further provides the use of the ribozyme-encoding vector of the present invention in the manufacture of a composition for the treatment of cell proliferative diseases such as cancer.
The present invention further provides the use of the ribozyme-encoding vector of the present invention in the treatment of cell proliferative diseases such as cancer.
A further object to the present invention is the use of the protein of the present invention in identifying the receptor or receptors of the protein or of a protein complex comprising the protein. Methods for identifying receptors are well known to those skilled in the art and have been widely described in the literature. However, basically there are three major ways of identifying receptors:                i. Test all known receptors that bind to similar molecules. This is particularly useful for the protein encoded by the DNA sequences shown in FIG. 1 and FIG. 2, as VEGF has been found to have a similar sequence.        ii. Perform a binding purification step. For example, the protein of the present invention or a protein complex comprising the protein of the present invention can be immobilized on to a solid support and numerous possible receptor molecules, especially membrane proteins, are then passed over the solid support. A binding purification procedure is described in Schuster et al. (1995) Brain Res. 670:14-28.        iii. By screening expression libraries in order to find cells lacking the receptor or receptors and then utilizing the receptor cloning method described by Seed and Aruffo (1987) Proc. Natl. Acad. Sci. USA 84:3365-3369.        
Other methods are also known to those skilled in the art and can be used in order to find the receptor or receptors.
On identifying the receptor or receptors it will be possible to design drugs that block or enhance the activity of the receptor or receptors and produce antibody molecules that block the receptor or receptors. Once the DNA sequence of the receptor or receptors are known, a number of gene therapies may be designed for correcting errors in the receptor or receptors, or for blocking expression of the receptor or receptors.
The present invention further provides the use of the protein of the present invention in an assay for identifying antagonists or agonists of the protein which may be used as drugs in the treatment of cancer and developmental disorders respectively. Assays for identifying such potential drugs are frequently used and are well known to those skilled in the art. An example of such an assay is clearly described in Tsunoda et al. (1994) Anti-cancer Res. 14:2637.
The present invention further provides the use of the nucleotide molecule, antisense nucleotide molecule, protein, or antibody molecule of the present invention, or any combination thereof, in diagnosing a pathological state or a predisposition to a disease.
The nucleotide molecule or antisense nucleotide molecule of the present invention may be used in determining the presence of the gene corresponding to the nucleotide molecule or in determining the amount of RNA transcribed from the gene.
The protein of the present invention may be used in an assay for determining the amount of protein encoded by the gene corresponding to the nucleotide molecule of the present invention.
The antibody molecule of the present invention may be used in an assay for determining the amount of protein encoded by the gene corresponding to the nucleotide molecule of the present invention. An example of an assay for determining the amount of protein using the antibody molecule of the present invention is a competitive binding assay.
By determining the presence of the gene corresponding to the nucleotide molecule of the present invention or the transcribed RNA or the protein encoded by the gene, it is possible to diagnose a pathological state or a predisposition to a disease caused by the presence of the gene or the overexpression of the gene.
The present invention further provides the use of the nucleotide molecule of a present invention in the generation of transgenic animals. In particular, the invention provides the use of such nucleotide molecules for the generation of non-human transgenic animals, especially transgenic mice.
Transgenic animals can be generated which are suitable as models for research. For example, transgenic animals which overexpress the nucleotide molecule of the present invention could be used in order to determine what effects overexpression will have. Alternatively, transgenic animals can be generated where the native nucleotide molecule of the present invention is “knocked out”. The effect of “knocking out” the nucleotide molecule could then be investigated.
Methods for generating such transgenic animals are well known to those skilled in the art and can be easily performed given that the nucleotide molecules to be overexpressed or “knocked out” are disclosed herein.
The transgenic animals of the present invention could also be subsequently bred with either Fos overexpression mice or Fos “knocked out” mice, in order to determine the effects of altered Fos control.
The present invention also provides a nucleotide molecule comprising all or part of the sequence shown in any one of FIG. 1 (SEQ ID NO:1) or 2 (SEQ ID NO:3). The nucleotide molecule comprising all or part of the sequence shown in any one of FIG. 1 (SEQ ID NO:1) or 2 (SEQ ID NO:3) may encode a protein or may be non-coding. Preferably, the nucleotide molecule additionally encodes the control sequences of the Fos gene corresponding to the nucleotide sequence shown in any one of FIG. 1 (SEQ ID NO:1) or 2 (SEQ ID NO:3). It is further preferred that the nucleotide molecule encodes a sequence which confers Fos regulation to a gene. It is particularly preferred that the nucleotide molecule comprises the sequence TGACTCA.